Channel Failure Acknowledge; Max. Readback Time Dark Test - Siemens SIMATIC S7-1500 Manual

Parameters/address space
4.2 Explanation of parameters
4.2.3.3

Channel failure acknowledge

Use in S7-1500 F-CPUs
This parameter is only relevant if the fail-safe module is operated on an S7-1500 F-CPU, and
can only be set if the F-parameter "Behavior after channel fault" is set to "Passivate channel"
and the F-parameter "Reintegration after channel fault" is set to "Adjustable".
The value of this parameter specifies how the channel should react to a channel fault:
● Manual: A channel is not reintegrated until after manual acknowledgment.
● Automatically: The channel is reintegrated automatically after a channel fault. Manual
acknowledgment is not necessary.
Use in S7-300/400 F-CPUs
The value of this parameter is not relevant in the case of operation on S7-300/400 F-CPUs.
There you set the corresponding property at the F-I/O DB by means of the ACK_NEC tag.
For detailed information about the F-I/O DB, refer to the SIMATIC Safety – Configuring and
Programming (http://support.automation.siemens.com/WW/view/en/54110126) manual.
4.2.3.4

Max. readback time dark test

Function
Dark tests are shutdown tests with bit pattern test.
For a dark test, a test signal is switched to the output channel while the output channel is
active (output signal "1"). The output channel is then switched off briefly (= "dark period") and
read back (for PM operation, P- and M-readback, for PP operation only PP-readback). A
sufficiently slow actuator does not respond to this and remains switched on.
①
Image 4-1
22
Readback (P-switch and M-switch do not switch simultaneously.)
Functional principle of the dark test (PM switching)
Digital output module F-DQ 8x24VDC/2A PPM (6ES7526-2BF00-0AB0)
Manual, 01/2016, A5E03858037-AA